The purpose of this study was to explore the correlations between particular teacher collaborative actions and teachers’ sense of self-efficacy. Additionally, descriptive analyses provided a snapshot of current collaborative action-taking across US schools, and elucidated teachers’ present sense of self-efficacy. This study utilized existing data from the 2013 Teaching and Learning International Survey (sponsored by the OECD), which was completed by 1,926 lower secondary teachers from just over 120 different American schools. Multivariate correlational analysis confirmed that frequency of US teachers’ participation in collaborative actions significantly correlated to higher levels of teacher self-efficacy. Actions with the highest correlations included: taking part in collaborative professional learning, working with other teachers to ensure common standards in evaluations for assessing student progress, engaging in joint activities across different classes, and collaboratively discussing the learning development of specific students. Descriptive analysis suggests that US teachers have an overall positive sense of self efficacy related to their instructional practices, ability to engage students, and classroom management skills. Differences in self-efficacy and participation in collaborative action-taking are evident by age, experience, and gender. While age and experience bring about greater sense of teacher self-efficacy, they also relate to decreases in participation in collaboration. This study concludes with a discussion regarding the implications of its findings, including recommendations for policy, practice, and future research.